United Nations, Sept 19 (AP) Iran, Israel and the five confirmed nuclear powers are part of a network to detect signs of testing of a new atomic bomb, in a positive sign of cooperation in the bid to halt the spread of such weapons, the head of the Nuclear Test Ban Treaty organisation said.

The monitoring network has not been widely reported nor have its participants, including Iran, which the West believes is pursuing nuclear weapons, and Israel, which is widely believed to possess a nuclear arsenal but won't say as much.

Tibor Toth told a news conference that a system to verify atomic blasts that was started in 2000 now has 270 monitoring facilities and expects to increase the number to 340.

New York: Iran, Israel and the five nuclear powers that are permanent Security Council members are part of a global network to detect signs of testing of a new atomic bomb, a positive sign of cooperation in the bid to halt the spread of such weapons, the head of the Nuclear Test Ban Treaty organisation said on Friday.

The monitoring network has not been widely reported nor have its participants, including Iran, which the West believes is pursuing nuclear weapons, and Israel, which is widely believed to possess a nuclear arsenal but won't say as much.

Tibor Toth said at a news conference that a system to detect and verify atomic blasts that was started in 2000 now has 270 monitoring facilities and expects to increase the number to 340.

The stations rely on four technologies: seismic, sensing the shock waves of an underground blast; hydroacoustic, listening for underwater explosions; infrasound, picking up the low-frequency sound of an atmospheric test; and radionuclide detection, sampling the air for a test's radioactive byproducts.

The data is transmitted to the Vienna headquarters of the Comprehensive Test Ban Treaty Organisation and relayed to its signatory nations, including the US, which signed the pact in 1996, only for the Senate to reject it three years later.

Toth called the verification system an important step to address concerns of nuclear and non-nuclear states, and noted that it monitored North Korea's nuclear tests in 2006 and 2009 "very well”.

Toth spoke to reporters ahead of a high-level meeting on September 24-25 on the sidelines of the UN General Assembly's annual ministerial meeting to press North Korea, India and Pakistan to first sign and then ratify the Comprehensive Test Ban Treaty, and to press the other six countries who have signed it to ratify it.

Major nuclear powers, including the United States, have observed moratoriums on testing since the 1990s, but India, Pakistan and North Korea all have tested bombs since the treaty was negotiated and opened for signatures in 1996.

The treaty has been signed by 181 countries and ratified by 149, but it cannot take effect until it is ratified by nine key holdouts — the US, China, North Korea, Iran, Israel, India, Pakistan, Indonesia and Egypt.

"I am very much optimistic because during the last 2-2 1/2 years we see a momentum building," he said. "We need action, action, action and leadership, leadership, leadership."

Toth praised President Barack Obama's April 5 speech in Prague in which he vowed to "immediately and aggressively" pursue treaty ratification by the Senate and to work with allies and other countries needed for ratification.

He said he was also encouraged that Indonesia's Foreign Minister indicated the country would ratify the treaty and China's Foreign Minister said the government was "working on the entry into force of the treaty”.

"The ratification by the US will play a leadership role and that leadership role is important," Toth said.

"I would like to emphasise, if you set aside the United States, the other outstanding ratifications are missing from Asia and the Middle East," he said. "It's an important reminder that the security of these regions can be enhanced, in my judgment, by this treaty, which is capping any potential arms races ... through taking the oxygen from the development of new weapons."

Toth said the five confirmed nuclear powers on the Security Council — Russia, France, China, Britain and the United States — are providing one-third of the monitoring stations and for the first time "they are undertaking legally binding obligations to be exposed to verification."

The US is expected to put in place 42 stations, and during the last 8 years has already started operating 39 of them, he added.

"Iran is contributing with monitoring stations which are installed," Toth said, adding that his organisation was working with Iran on getting the stations operational.

Toth said, "Ratification of the treaty is a clear indication that countries have no intention to use nuclear energy in any other way than the peaceful use of nuclear energy ... so from that point of view it's important that Iran ratifies the treaty."

He said Israel "did not say no" to ratifying the treaty and is "positively contributing with monitoring stations to our work and scientific and technical involvement in our work."

"It would be an extremely important step_ and the right step in the right direction in my judgment — if Israel ratified the treaty," Toth said.

India, Pakistan and North Korea have not even signed the treaty and Toth urged them to consider whether the test ban was in their national interests.

He welcomed the "positive soul-searching" in India and stressed that even if a country ratifies the treaty before the United States, "it is not risking any strategic security interest" because the test ban doesn't come into force until all nine key holdout countries sign it.